The utility industry has long grappled with the issue of reading utility meters without inconveniencing a homeowner. The issue was particularly noticeable as it related to reading water meters in geographic areas subject to freezing temperatures. In order to prevent damage from the freezing temperatures, the water meters were installed inside the residences. Thus, a representative of the utility company needed access to the inside of the residence in order to read the meter, creating an inconvenience for both the homeowner and the utility company.
In an effort to alleviate the problems associated with physically reading utility meters, utility companies deployed remote meter transmission units. In general, a remote meter transmission unit may remotely read a utility meter and transmit meter readings or other meter related information, directly or indirectly, back to a utility company. The remote meter transmission units often transmit the meter readings via radio frequency signals, such as to a central reading station, or a data collector unit. In some instances the radio frequency signal may be transmitted over relatively long distances, such as a mile or more. Thus, the remote meter transmission units may require a robust antenna capable of transmitting the meter readings the necessary distances.
In some instances the remote meter transmission unit and antenna may be housed within the meter itself. Alternatively the remote meter transmission unit and antenna may be housed within a separate enclosure. In either case the antenna may be subject to size constraints. In addition, the antenna may often be surface mounted in order to meet the size constraints and/or in order to effectively transmit the signal, such as to a data collector unit. Often the antennas may be situated near other components of the remote meter transmission unit or components of the meter itself. The close proximity to the components may affect the efficiency of the antenna in radiating the desired signals. For example, materials such as metals, plastic or concrete can affect the radiating pattern of an antenna. In addition, the proximity of the materials to the antenna may cause the antenna to become detuned. That is, the materials may change the frequency at which the antenna propagates signals. A detuned antenna may not be capable of effectively transmitting the meter readings, such as to a data collector unit. The antenna can also suffer from detuning if it is situated near metallic structures, such as the utility meter itself.
Thus, in order for an antenna to be properly suited for remote meter reading applications, the design of the antenna should achieve a balance between physical size, radio frequency performance and mechanical strength such that the antenna has a small form factor capable of being surface mounted without suffering from near field detuning.